Hardened Hex head bolts with “23” head marking attach hinges to pillars
Hardened Philips head Bolts attach hinges to doors
5/16″-18 Threads
Dark Phosphate Coating
See below for specific applictions
Correct door hinge bolt set for mounting steel and cast iron or aluminum hinges . Hinge to pillar bolts are 5/16-18 with "23" head marking. Hinge to door hex bolts have correct Phillips head.